cc: Generate tilings at other scales for impl-side painting

cc/picture_layer_tiling_set.h

Index: cc/picture_layer_tiling_set.h
diff --git a/cc/picture_layer_tiling_set.h b/cc/picture_layer_tiling_set.h
index 383884e1de1afca8038c2b1ad4cc3bc6af024c78..c4c9fc1cae003d71c6c27ea6f2c5adfc9a461bcb 100644
--- a/cc/picture_layer_tiling_set.h
+++ b/cc/picture_layer_tiling_set.h
@@ -26,12 +26,18 @@ class CC_EXPORT PictureLayerTilingSet {
   void SetLayerBounds(gfx::Size layer_bounds);
   gfx::Size LayerBounds() const;
 
-  const PictureLayerTiling* AddTiling(
+  PictureLayerTiling* AddTiling(
       float contents_scale,
       gfx::Size tile_size);
   size_t num_tilings() const { return tilings_.size(); }
   PictureLayerTiling* tiling_at(size_t idx) { return tilings_[idx]; }
 
+  // Remove all tilings.
+  void RemoveAll();

[danakj, 2013/01/08 23:27:16]

How about RemoveAllTilings() and RemoveTiling(Tiling*) ?

[enne (OOO), 2013/01/08 23:54:38]

Done.

+
+  void Remove(PictureLayerTiling* tiling);
+
+  // Remove all tiles, but keep all tilings.
   void Reset();

[danakj, 2013/01/07 22:35:56]

Maybe for separate CL, but this function name could say what it does.

[enne (OOO), 2013/01/08 01:08:00]

Which function? Reset does say what it does.  I can add a comment to Remove, if
that's what you mean.

[danakj, 2013/01/08 23:27:16]

// Remove all tiles, but keep all tilings.
void Reset();

could be

void RemoveAllTiles();
or
void RemoveAllTilesButNotTilings();

Reset() is just a little vague.

 
   void UpdateTilePriorities(
@@ -53,7 +59,8 @@ class CC_EXPORT PictureLayerTilingSet {
     Iterator(
       const PictureLayerTilingSet* set,
       float contents_scale,
-      gfx::Rect rect);
+      gfx::Rect content_rect,
+      float ideal_contents_scale);
     ~Iterator();
 
     // Visible rect (no borders), always in the space of rect,
@@ -70,11 +77,17 @@ class CC_EXPORT PictureLayerTilingSet {
     Iterator& operator++();
     operator bool() const;
 
+    PictureLayerTiling* CurrentTiling();
+
    private:
+    int NextTiling() const;
+
     const PictureLayerTilingSet* set_;
     float contents_scale_;
+    float ideal_contents_scale_;
     PictureLayerTiling::Iterator tiling_iter_;
     int current_tiling_;
+    int ideal_tiling_;
 
     Region current_region_;
     Region missing_region_;